Chances are , someone you know takes a sleeping pill . One in four Americans takes a sleep aid every year , according to the National Sleep Foundation , and the numbers are even higher for women -- one in three uses some sort of sleep medication a few times a week .

Many sleeping pills stop working after a few hours , and most should not be combined with other medications .

Why do women have such trouble sleeping ? The reasons are as numerous as the passel of pills on the market : anxiety , depression , chronic illness , restless legs syndrome , sleep apnea , everyday exhaustion ... the list goes on and on . No wonder so many sleep aids are available .

But sleeping pills , while often quite helpful , are largely misunderstood . Many stop working after a few hours , for instance , and most should never be mixed with other meds . So if you take one of these drugs now -- or plan to in the future -- there are important questions you need to ask . Here , the answers .

Q : How do I know if I need a sleeping pill ?

A : More than a third of Americans experience occasional insomnia , which is defined as a few nights of restlessness , poor sleep , or trouble falling asleep . The general rule of thumb : If insomnia lasts a month and does n't get better , talk to your doctor , says Frisca L. Yan-Go , M.D. , director of the Sleep Disorders Center at Santa Monica-University of California , Los Angeles , Medical Center and Orthopaedic Hospital . She may recommend a pill for a short period , but do n't be surprised if she suggests some tests or other non drug treatment options first . Health.com : How much sleep do you need ?

For starters , your doc may have you visit a sleep specialist to rule out sleep apnea , a common breathing disorder that wakes sufferers several times a night , sometimes without them even knowing it . If you have apnea , you may need a sleeping device that gently forces air into your windpipe .

If you do n't have apnea , some docs recommend cognitive behavioral therapy : You work with a trained therapist to change how you think about sleep and learn sleep-inducing techniques -LRB- like how to set up your sleep space and what to do before bedtime -RRB- . Some studies say CBT is as effective as pills -- if not more -- and has no side effects . Health.com : Health risks of snoring and sleep apnea

`` Often people attribute everything bad that happens to them , including being angry and crabby , to lack of sleep , '' says Donna Arand , Ph.D. , clinical director of the Kettering Sleep Disorders Center in Kettering , Ohio . `` It puts such a burden on sleep that not sleeping gets blown out of proportion . '' CBT changes that kind of distorted thinking and in some cases is prescribed along with a pill .

Q : Should I try over-the-counter drugs before a prescription pill ?

A : Many sleep experts are n't fans of OTC sleep aids because the meds do n't usually help people with significant insomnia . And many -- like Nytol , Simply Sleep , Sominex , and Unisom -- contain antihistamines -LRB- similar to the allergy medicine Benadryl -RRB- that can have side effects like dry mouth and eyes and next-day grogginess , Arand says . OTC sleep aids are best for people who have occasional sleep problems . Note : Women who breast-feed should avoid them , as should the elderly , who sometimes are more sensitive to the effects of antihistamines .

Q : If I take a prescription pill and still ca n't fall asleep , can I take another ?

A : If you 're taking a short-acting drug , such as Sonata , Rozerem , or Ambien -- and it 's still early in the evening -- you can take another pill . Short-acting medications kick in and then fade out , which is why they are prescribed for people who have trouble falling asleep . Health.com : Is stress causing your insomnia ?

`` They last about three or four hours , so you could take another pill up until about 3 a.m. because it would metabolize before you wake up , '' says Ana Krieger , M.D. , a sleep specialist at New York University . -LRB- The timing depends on your sleep schedule , of course , and it 's always wise to check with your doctor , she adds . -RRB- Longer-acting drugs like the time-released Ambien CR or Lunesta -- for people who have trouble falling and staying asleep -- should n't be taken more than once a night .

Q : Is it safe for me to take a sleeping pill at 11 p.m. if I had a glass of wine or a cocktail around 6 p.m. ?

A : It 's probably OK , doctors say , but the sleeping pill wo n't work as well as it should . Here 's why : `` Alcohol becomes a stimulant about three to four hours after you drink it , so you 're actually working against your sleep medication , '' Arand says . `` It 's a terrible combination . ''

Never drink and then immediately take a sleep aid . Why ? Alcohol acts like a sedative at first , so you 'd essentially be getting a double dose of sedatives . This can dangerously slow your heart rate and lead to dizziness , fainting , and shallow breathing , which can deprive your body of oxygen and damage brain cells . Worst case : You may even stop breathing altogether . Health.com : 11 kinds of insomnia

Because everyone metabolizes food and alcohol at different rates , there are no safety absolutes when it comes to the minimum number of hours you should wait between consuming alcohol and taking a sleeping pill , experts say . `` But if you 're at a dinner party and really want a drink , have the alcohol early , '' Krieger says . `` Then eat dessert without any alcohol and wait as long as possible before taking your sleeping pill . ''

Q : Can sleeping pills give me nightmares ?

A : Not usually , Arand says , `` but some sleep meds can suppress dream recall . '' When you stop taking them , the dreams -LRB- and possibly nightmares -RRB- may return . The mechanism is n't fully understood , but once there 's a withdrawal -- even just when the dosage wears off during the night -- vivid dreams can occur .

Q : Can I safely take sleeping pills for several months ?

A : There are no known long-term health risks with most sleep aids , but some are more addictive than others .

`` The newer medications like Ambien C.R. , Sonata , Rozerem , and Lunesta have been approved by the Food and Drug Administration without a limit on how long they can be prescribed , '' Arand says . `` They have a small addiction potential , and some have been shown to be effective up to one year . '' The older sleeping pills with secobarbital -LRB- Seconal -RRB- and pentobarbital -LRB- Nembutal -RRB- pose a much higher risk of addiction .

Tolerance is a common problem with all sleeping pills : After taking them for a while , you need more than the usual dose to help you sleep , which may lead you to think you 're addicted . If the drug does n't seem to be working as well as it used to or if you 're taking more than your prescribed dosage , tell your doctor ; she can change or adjust your medication .

Q : I 've been taking sleeping pills for several months . What 's the best way to wean myself off ?

A : With your doctor 's help , gradually step down your meds . Generally , you want to reduce drugs by one clinical dose per week : If you 're taking 10 milligrams of traditional Ambien a night , start taking 5 mg a night for a week , Arand recommends . Next , cut that pill in half and take that amount for a week . Then , stop taking the drug altogether . Medications in pill -LRB- not capsule -RRB- form that are n't time-release versions are OK to split . -LRB- You can split Ambien , for instance , but not Ambien CR . -RRB-

Q : I 've heard of rebound insomnia . Is it really harder to fall asleep and stay asleep without pills if I 've taken them a few times ?

A : You might have some trouble , Krieger says , though it 's less likely with the newer pills -- these include Rozerem , Sonata , and Lunesta . `` Give it a few days to adjust after you stop taking the medication , '' Arand explains . If you still ca n't sleep , talk to your physician . Rebound insomnia is one of the reasons some experts recommend CBT over sleep medications .

Q : If I do n't want to use sleeping pills , are natural remedies worth trying ?

A : Yes , but do n't expect miracles . Melatonin , a sleep hormone your body makes naturally , and the herb valerian may be helpful -LRB- both are available at drugstores -RRB- , but some experts feel there 's a lack of research to back up the effectiveness of these supplements . Plus , they 're not regulated like drugs , so you do n't always know what you 're getting .

That said , if you want to try melatonin , take 0.2 to 1 mg about four hours before bedtime : `` It 's safe to take every day , '' Krieger says . `` As we age , our bodies secrete less of it , so taking a supplement can be helpful . '' Melatonin may be particularly beneficial when you travel several time zones to the east -LRB- like Europe -RRB- and have trouble falling asleep . As for valerian , there 's no recommended dosage , and it 's not clear how the herb works . Before using any supplement , check with your doctor ; combining them with other medications -- sleeping pills or otherwise -- can be risky .

Enter to win a monthly Room Makeover Giveaway from MyHomeIdeas.com

Copyright Health Magazine 2009

@highlight

One in four Americans takes a sleep aid every year , organization says

@highlight

Some studies say cognitive behavioral therapy works as well as pills

@highlight

Expert : OTC sleep aids are best for people with occasional sleep problems .

@highlight

Never drink alcohol and then immediately take a sleep aid